Recently i faced some Outlook 2016 functionality issues. It became impossible to sent / receive email.
In Outlook 2016 options there was a message ‘Upgrade in progress’ This could be there for days without any change.
Some websites are saying that opening Outlook in /safe mode is resolving the issue, this was not the case for me.
The solution for me was:
start -> run -> regedit
go to HKEY_CLASSES_ROOT\Installer\Components\F1291BD604B860441AB89E60BDEE0F9C
right click -> permissions
‘add’ the current user or ‘everyone’ and give it READ permissions.
Open Outlook 2016 and all should work fine.